Hydromecanical piercing perforator  and method of operation thereof

ABSTRACT

Proposed devices provide for a jetting process of formation critical areas after opening up a column, increasing a perforator&#39;s punch power and reliability, significantly preventing accidents. A hydro-mechanical piercing-type perforator includes a casing containing a hydraulic cylinder with a pusher, an operating tool radially movable and capable of interaction with the pusher. The tool is designed as a puncher, placed on a piston (plunger), mounted in a camera. The tool includes at least one through hydraulic channel and a jet. The camera is hydraulically connected with the cylinder. A proposed method for operating the perforator includes supplying a working fluid to the perforator through the column, creating pressure of the working fluid for an extension mechanism actuating the tool, extending the tool by applying the pressure through a piston rod system, to the piston with the puncher, and applying pressure to the piston through the hydraulic cylinder to the chamber.

FIELD OF THE INVENTION

The proposed invention relates to drilling and well operations, in particular to the design of devices for drilling-in of productive stratums through a piercing perforation, and may be used in the construction and repair of wells for various purposes.

BACKGROUND OF THE INVENTION

In the prior art, there are known devices for perforation of wells by piercing, disclosed in Russian Federation Patents RU 2129655 C1, IPC 6 E21B 43/112, 27 Apr. 1999; RU 2355877 C2, IPC E21B 43/112, 20 May 2009, including the casing, tool pistons with piercing elements—punchers with the mechanism of their extension, which is based on the principle of fluid expansion during heating and making of its high-pressure supplied to the tool pistons, as a result the radial moving of tool pistons and extension of pushers happen. Significant disadvantages of these devices are low productivity, insecurity and design complexity, including energy drive with the heat source. Moreover, such perforator designs exclude the jetting process possibility of critical area of formation immediately after opening up of the column, which reduces the efficiency of the opening up.

In the prior art a large number of piercing perforating devices are known, their method of operation is based on the extension of pushers by hydraulic mechanism disclosed in Russian Federation Patents: RU 2373382 C1, IPC E21B 43/112, 20 Nov. 2009; RU 2172394 C1, IPC 7 E21B 43/112, 20 Aug. 2001; RU 2069741 C1, IPC 6 E21B 43/112, 27 Nov. 1996; RU 2069740 C1, IPC 6 E21B 43/112, 27 Nov. 1996, RU 2043486 C1, IPC 6 E21B 43/114, 10 Sep. 1995. The devices include a casing, comprising a system of cameras, pistons and rods, leading the working fluid coming to perforator through the column of tubings to the punch piston. Such hydraulic mechanisms often have a low penetration. In order to increase the penetration they can include pressure boosters, which complicate the devices design and increase manufacturing costs, the productivity and efficiency of devices are not high enough at the same time. Moreover, when using such perforators with boost pressures the tightness problems of all design units and accelerated wear of the seal elements of the pistons are arisen.

In the prior art, there is known a device for creating of perforating channels in a casing string according to Russian Federation Patent RU 2395671 C1, IPC E21B 43/112, 27 Jul. 2010. The device comprises tube and support housings, a cylinder connected to the support housing and comprising an actuating piston with a return spring and a slip pusher, equipped with working cutters longitudinally moveable in relation to the slip pusher when actuated by the support housing, the valve gear with its casing, mounted above the cylinder, and a secondary return spring, and the tube housing is connected to the piston to perform constrained longitudinally movement. The cylinder above the support housing is provided with a ring seat, the piston has a collar, and the return spring is mounted between the external collar of the piston and the ring seat of the cylinder. The tube housing has a seat above the ring collar of the piston, while the secondary return spring is mounted between the seat and the piston in the cylinder. The casing of valve gear is fixedly connected with tube housing and it has valve seat at the top and leaky inside seal at the bottom. The spring is applied to press the valve to the seal of the valve gear casing from the internal seat, so that to hold a liquid column forcing the valve in the perforation range.

The connection of valve gear and tube housing can be made built-up (for example, thread) for convenience of assembling and disassembling. The number of cylinders and their respective actuating pistons is selected from the necessary forces for the opening up of the casing string of well: the thicker wall of the casing string, the greater a number of cylinders with the actuating pistons need to use. The unauthorized overflows of liquid in the device are excepted by seals.

This device hasn't disadvantages of hydraulic piercing-type perforators, it has high punch capability, sufficient power and it opens up the column effectively, but its design exclude the jetting process possibility of critical area of formation immediately after opening up of the column, which reduces the efficiency of the opening up.

To offer a more powerful device for drilling-in the effort is made in the useful model according to Russian Federation Patent RU 115407 U1, IPC E21B 43/114, 27 Apr. 2012. This device is the closest analog of the proposed invention and it is herein further referred to as a ‘prototype’.

The device for creating of perforating channels in the well comprises the casing, slip with grooves, at least two placed one behind the other hydraulic cylinder connected with piston rods, one of which is spring-loaded, and at least two cutters with jets and cutting holder, placed in grooves of support and slip with ability of radial reciprocating moving, the casing is made by slip and walls of hydraulic cylinders, in which piston rods are made with an axial channel connected downpipe with their piston cavities and tubes with jets of cutters through channels of cutting holders, the support of which is connected to the piston rod, spring-loaded downward relative to the hydraulic cylinder.

The disadvantage of the device according to the prototype is the unreliability of the working fluid supply design in the jet nozzle. There is a high capability of pipe break or seal failure of pipes in operating conditions, therefore alluvium caverns would be impossible to execute not only, but also the column is opened up, because of the working fluid from the hydraulic cylinders begins to flow through the tube when efforts to create an operating pressure. This can lead to emergency in well.

OBJECT AND SUMMARY THE INVENTION

The objective of the proposed invention is to create a highly efficient and reliable design of hydro-mechanical piercing-type perforator and perforator's method of operation, providing a guaranteed opening up of the production string and the possibility of subsequent jetting process of critical area of formation in the area of opening up.

The proposed invention achieves the following technical result:

-   -   1. Increasing the punch force, improving the quality of the         opening up of the production string, increasing productivity of         perforator.     -   2. Increasing the perforation efficiency and improving         hydrodynamic connection to the layer due to the guaranteed         possibility of the jetting process of critical area of formation         immediately after opening of the column.     -   3. Reducing accidents, increasing the reliability of perforator.

The mentioned technical result is achieved by providing the combined method of puncher ejection in the piercing-type perforator, this method based on hydromechanical principle of operation: tool piston or plunger of puncher are affected by the mechanical force of the slip pusher and the hydraulic pressure force of fluid, supplied to the process chamber of tool piston (plunger).

Hydro-mechanical piercing-type perforator comprises a casing, at least one operating hydraulic cylinder placed in it, at least one slip pusher, at least one operating tool, which includes at least one through hydraulic channel and at least one jet mounted with the interact capability to the slip pusher and radial moving.

According to the invention, the operating tool is designed as piston with puncher (tool piston), equipped by seals, mounted in the camera, or plunger with the puncher (tool plunger) mounted in the camera, equipped by seals, and the camera is designed with capability of hydraulic connection with the operating hydraulic cylinder.

The connection of the process chamber of tool piston (plunger) with a hydraulic cylinder can be carried out by different ways constructively.

The camera is connected with operating hydraulic cylinder by means of one or several channels made in the slip pusher.

The camera is connected with operating hydraulic cylinder by means of areas (flats, chamfers) or grooves made on the external surface of the slip pusher.

The camera is connected with operating hydraulic cylinder by means of cavities, made on the internal surface of perforator casing or the surface of slip pusher.

The camera is connected with operating hydraulic cylinder by means of one or several channels made in the perforator casing.

The slip pusher of perforator can be equipped by seals and it is a piston.

The movement cavity of slip pusher can be equipped by seals, and slip pusher can be a plunger.

The method of operation of hydro-mechanical piercing-type perforator comprises working fluid supply to perforator through the column of tubings, operating pressure creation for actuating the extension mechanism of the operation tool, extension of operation tool and implementation of perforation. According to the method of the invention, the extension of the operation tool is made by impact of working fluid pressure through the piston rod system to the slip pusher, the slip pusher is made impact on the tool piston (plunger) with a puncher, and also the impact on the tool piston (plunger) of working fluid supplied under pressure through a hydraulic cylinder of perforator to the process chamber of tool piston (plunger).

Due to an implementation in the device the operating tool in the form of a piston with puncher or plunger with puncher (tool piston/plunger) the supply of operating liquid pressure on operating tool and the creating of additional force, directed at the extension of the operation tool is become available. Due to an implementation of camera of the tool piston/plunger with capability of hydraulic connection with operating hydraulic cylinder the operating liquid supply at camera from hydraulic cylinder for influence on tool piston/plunger is implemented. Thus, proposed design and the method of operation of perforator are ensured supply at puncher a double force, which is combined the mechanical force of slip pusher and hydraulic force of operating liquid to the tool piston/plunger. Thus, penetration of puncher is increased, the opening up quality of production string is improved.

Moreover, due to implementation of camera of tool piston/plunger with capability of hydraulic connection with operating hydraulic cylinder the supply of operating liquid to hydraulic channel of jet nozzle is made, so that immediately after opening up of the column the jetting process of critical area of formation can be made, that significantly increases the efficiency of the opening up.

If slip pusher of perforator is made in form of a piston or plunger, it can carry out function of additional hydraulic cylinder, thereby the operating force applied to the tool piston/plunger is increased.

The proposed design and the method of operation of device is characterized in simplicity and reliability, which allows a trouble-free operation of perforator.

BRIEF DESCRIPTION OF DRAWINGS

The claimed device in several variants of its implementation is shown in FIGS. 1-8:

FIG. 1—the device in longitudinal section in a transportation position;

FIG. 2—the device in longitudinal section in the operating position;

FIG. 3—the version of device with the channels formed in the slip pusher;

FIG. 4—the version of device with areas (flats) made on the external surface of the slip pusher;

FIG. 5—the version of device with areas (chamfers) made on the external surface of the slip pusher;

FIG. 6—the version of device with grooves made on the external surface of the slip pusher;

FIG. 7—the version of device with cavities, made on the internal surface of perforator casing and the surface of slip pusher;

FIG. 8—the version of device with channels made in perforator casing.

DETAIL DESCRIPTION OF PREFERRED EMBODIMENTS OF THE INVENTION

The device according to the invention comprises casing 1, at least one operating hydraulic cylinder 2, placed in it, at least one slip pusher 3, at least one operating tool 4, which includes at least one through hydraulic channel 5 and at least one jet 6. The operating tool 4 is mounted with the interact capability to the slip pusher 3 and radial movement. The operating tool 4 is designed as a plunger 7 with puncher 8 (of tool plunger 7), mounted in camera 9, the camera 9 is designed with capability of hydraulic connection with the operating hydraulic cylinder 2.

The connection of process chamber 9 of tool plunger 7 with hydraulic cylinder can be carry out by means of channels 10, made in slip pusher 3 by means of areas (flats 11, chamfers 12) or grooves 13, made on the external surface 14 of the slip pusher 3 by means of cavities 15, made on the internal surface 16 of perforator casing 1 or on the surface 14 of slip pusher 3, or, for example, by means of one or several channels 10, made in perforator casing 1.

The device operates as follows. The perforator on the column of tubings is lowered into the well, the working fluid is supplied to perforator, operating pressure is created for actuating the extension mechanism of operating tool 4. The extension of operation tool 4 is made by impact of working fluid pressure through the piston rod system included one or several hydraulic cylinders 2, to the slip pusher 3, the slip pusher 3 is made impact on tool piston/plunger 7 with a puncher 8, and also the impact on the tool piston/plunger 7 of working fluid supplied under pressure through a hydraulic cylinder 2 of perforator to the process chamber 9 of tool piston/plunger 7. As a result of supply to tool piston/plunger 7 of the combined hydromechanical force it moves radially, pushing the puncher 8 and the opening up of the column is performed. After that, the processing of critical area of formation is executed out if it is necessary through the jet nozzles 6.

Upon completion of work the device is brought in the transportation position by known manner for example as follows: the working fluid pressure is released, under the influence of one or several springs 18 operating hydraulic cylinder 2 and slip pusher 3 are moved to uppermost position, by the instrumentality of a T-shaped connection 17 or connection “dovetail” the slip pusher 3, moving up, retracts an operating tool 4 into the casing, placing it in the transportation position.

The perforator is removed on surface or transferred to a new perforation interval. 

I claim:
 1. A hydro-mechanical piercing-type perforator comprising: a casing; at least one operating hydraulic cylinder placed in it; at least one slip pusher; at least one operating tool, mounted with the interact capability to the slip pusher and radial movement, characterized in that the operating tool is designed as a puncher, placed on piston or plunger, mounted in the camera, and the camera is designed with capability of hydraulic connection with the operating hydraulic cylinder; said operating tool equipped: at least one through hydraulic channel; at least one jet;
 2. The hydro-mechanical piercing-type perforator according to claim 1, characterized in that the camera is connected with operating hydraulic cylinder by means of one or several channels made in the slip pusher.
 3. The hydro-mechanical piercing-type perforator according to claim 1, characterized in that the camera is connected with operating hydraulic cylinder by means of areas (flats, chamfers) or grooves made on the external surface of the slip pusher.
 4. The hydro-mechanical piercing-type perforator according to claim 1, characterized in that the camera is connected with operating hydraulic cylinder by means of cavities, made on the internal surface of perforator casing or the surface of slip pusher.
 5. The hydro-mechanical piercing-type perforator according to claim 1, characterized in that the camera is connected with operating hydraulic cylinder by means of one or several channels made in the perforator casing.
 6. The hydro-mechanical piercing-type perforator according to claim 1, characterized in that the slip pusher has seals and it is a piston.
 7. The hydro-mechanical piercing-type perforator according to claim 1, characterized in that the cavity of movement of slip pusher has seals, and slip pusher is a plunger.
 8. A Method of operation of hydro-mechanical piercing-type perforator including working fluid supply to perforator through the column of tubings, operating pressure creation for actuating the extension mechanism of the operation tool, extension of operation tool and implementation of perforation, characterized in that the extension of the operation tool is made by impact of working fluid pressure through the piston rod system on the slip pusher, the slip pusher is made impact on tool piston or plunger with a puncher, and also the impact on the piston/plunger of working fluid supplied under pressure through a hydraulic cylinder of perforator to the process chamber of tool piston/plunger. 